This invention relates generally to window shades and more particularly to a window shade construction for mounting a window within a window frame unit for use as a day/night type shade, for example, in a home or in a vehicle such as a van.
The prior art has proposed a number of venetian blind-type window coverings including ones for use in vehicular or van windows. Such venetian blind constructions are shown for example in my prior U.S. Pat. Nos. 4,444,239 and 4,506,476. These prior U.S. patents illustrate venetian blind assemblies which are attachable respectively to a window frame and directly to the glass or other transparent member of the window itself. In the latter case, the window may be hingedly mounted for opening and closing relative to the fixed frame and surrounding wall, whereby the window blind attached thereto moves with the window.
The present invention provides a shade-type of window covering as an alternative to the venetian blind-type of window covering. However, it will be appreciated that some of the same considerations as to mounting relative to a window or window frame, are applicable to such a shade type of structure as well.
It is also often desirable when using window shades to provide for continuously variable positioning of the shade relative to the window. That is, the shade preferably should be movable to positions respectively substantially fully covering the window and fully exposing the window and also adjustable to any desired position therebetween. Moreover, it is often desirable to provide a translucent type of shade for daytime use for permitting outside light to enter while preventing visual observation of the interior of the home or vehicle from the outside. On the other hand, for nighttime use, it is desirable to utilize opaque shades for preventing viewing of a lighted interior.